You can come from the airport into the city in 3 ways: taxi, bus or train. Here you can find all options explained in detail: https://www.barcelona-life.com/barcelona/airport

As regarding moving inside the city, one can find many metro lines, bus, tram and trains in Barcelona.

Metro opening hours:

Monday to Thursday: 5.00 am until midnight.

Fridays and eves of public holidays: 5.00 a 2.00 am.

Saturdays: from 5.00 am and runs all night.

Sundays: until midnight.

Public holidays during the week: until midnight.

An alternative transportation mode is bicycle. ‘’Bicing’’ is Barcelona’s public bicycle borrowing system for permanent residents only. Barcelona residents can register online to get a Bicing city bike membership card. The cost is around €50 a year.